Which
of the following statements are true about Public-key cryptography? Each correct answer represents
a complete solution. Choose two.
A.
Data encrypted with the secret key can only be decrypted by another secret key.
B.
The secret key can encrypt a message, and anyone with the public key can decrypt it.
C.
The distinguishing technique used in public key-private key cryptography is the use of
symmetric key algorithms.
D.
Data encrypted by the public key can only be decrypted by the secret key.
Explanation:
Each user has a pair of cryptographic keys: a public key and a private key. The private
key is kept secret, whereas the public key may be
widely distributed. A message encrypted with a recipient’s public key cannot be decrypted by
anyone except the owner of that key and the
person associated with the public key used. This is used for confidentiality. A message signed with a
sender’s private key can be verified by
anyone who has access to the sender’s public key.
Answer options A and C are incorrect. Because of the asymmetric behavior of the keys, the secret
key can encrypt a message, and anyone
with the public key can decrypt it. The distinguishing technique used in public key-private key
cryptography is the use of asymmetric key
algorithms because the key used to encrypt a message is not the same as the key used to decrypt it.